A method is disclosed for recovering a useful gas from a gas mixture including a useful gas and at least one secondary gas. The gas mixture is first compressed and transferred into a pressure vessel where cooling occurs. Then, from the pressure vessel, a secondary-gas containing gas phase is removed and condensed useful gas is transferred into a purification vessel. In the purification vessel, the condensed useful gas is then purified. A plant is disclosed for recovering a useful gas from a gas mixture. Finally, the use of a plant for carrying out a method for recovering a useful gas from a gas mixture is disclosed.

In one embodiment, a carbon dioxide capturing system includes an absorber to discharge an absorption liquid having absorbed carbon dioxide, a regenerator to discharge the absorption liquid having released the carbon dioxide, a first line to introduce the absorption liquid discharged from the absorber to the regenerator, a second line to introduce the absorption liquid discharged from the regenerator to the absorber, and a heat exchanger to exchange heat between absorption liquids flowing in the first and second lines. The system further includes a bypass line to branch from the first line between the absorber and the heat exchanger and introduce the absorption liquid to the regenerator without passing through the heat exchanger, a valve on the bypass line, an instrument to measure a value indicating a state of the regenerator, and a controller to control a degree of opening of the valve based on the measured value.

A carbon capture system includes a Carbonator for adsorbing carbon dioxide with a carbon dioxide lean sorbent generating a carbon dioxide rich sorbent, a first Calciner for thermally decomposing a carbon dioxide rich sorbent into a carbon dioxide lean sorbent and carbon dioxide, a supply of raw material to be calcined into the first Calciner containing a carbon dioxide rich sorbent, a connection between the first Calciner and the Carbonator, a second Calciner for thermally decomposing a carbon dioxide rich sorbent into a carbon dioxide lean sorbent and carbon dioxide, a connection between the Carbonator and the second Calciner, and a connection between the second Calciner and the Carbonator.

The present invention is a process for removing carbon dioxide from a compressed gas stream including cooling the compressed gas in a first heat exchanger, introducing the cooled gas into a de-sublimating heat exchanger, thereby producing a first solid carbon dioxide stream and a first carbon dioxide poor gas stream, expanding the carbon dioxide poor gas stream, thereby producing a second solid carbon dioxide stream and a second carbon dioxide poor gas stream, combining the first solid carbon dioxide stream and the second solid carbon dioxide stream, thereby producing a combined solid carbon dioxide stream, and indirectly exchanging heat between the combined solid carbon dioxide stream and the compressed gas in the first heat exchanger.

Disclosed is a system and method of separating and collecting acid gas such as carbon dioxide in which the energy consumption in a stripping column for regenerating an absorbent may be reduced. In the system and method, the energy consumption may be reduced using heat generated during the acidic gas separation and collection processes. In the system and method, a low-temperature condensate from a condenser may be preheated by heat exchange with a high-temperature processed gas, and then supplied into the stripping column, thereby to reduce the heat duty of a reboiler and the energy consumption in the condenser for cooling. A partial flow of a carbon diode-absorbed absorbent from an absorber column may be preheated by heat exchange with high-temperature processed gas from an upper portion of the stripping column, and then supplied into the stripping column, thereby to further reduce the heat duty of the reboiler.

Systems and methods are provided for regenerating a bed containing absorbed and/or adsorbed CO.sub.2 using a low value steam stream. The steam stream can have a pressure of 10 kPa-a to 50 kPa-a and a temperature of 46° C. to 81° C. The steam stream can be used to displace CO.sub.2 from the bed, resulting in formation of a low pressure stream including water vapor and CO.sub.2. The stream containing water vapor and CO.sub.2 is then passed through a liquid ring pump that includes an associated ring cooler. The ring pump provides the suction necessary to draw the low value steam stream through the bed to displace the CO.sub.2. Due to the nature of operation of the liquid ring pump, the majority of water in the steam containing H.sub.2O and CO.sub.2 can be removed within the liquid ring pump, resulting in production of a stream comprising 90 vol % or more of CO.sub.2 at a pressure of 90 kPa-a or more. An example of a bed that can be regenerated using a low value steam stream is a bed that corresponds to a liquid amine that is coated on/covering/impregnated into a porous solid, so that the liquid amine remains substantially in place during a cycle of sorption and desorption of CO.sub.2.

Compressed rich natural gas is divided into a cooling gas stream and a fuel gas stream. The cooling gas stream is depressurized. The cooling gas and the fuel gas are then heat exchanged to provide a first cooling step to the fuel gas. The cooled fuel gas continues into a second cooling step in a second heat exchanger, and then flows into a separator vessel where liquids are removed from the bottom of the separator and conditioned fuel gas exits the top of the separator. The conditioned fuel gas from the separator and produced from its influent is depressurized and heat exchanged to provide the second cooling fluid for the second heat exchanger.

A method for obtaining water from ambient air is disclosed that includes bringing the ambient air into contact with at least one liquid absorption agent for absorbing at least one part of the water contained in the ambient air, conveying an absorption agent diluted by the absorbed water to a first heat exchanger, and transferring the diluted absorption agent in at least one desorption device. Water desorbed in the desorption device is transported to the first heat exchanger, the desorbed water being cooled by means of the diluted absorption agent by means of the first heat exchanger. A device for obtaining water from ambient air is also disclosed.

The present invention relates to a process for thermally separating a mixture comprising a first main component and a second main component, where the boiling point of the first main component is lower than the boiling point of the second main components. The invention further relates to a system for thermal separation comprising a computer for control of the thermal separation which is set up to control the process of the invention. By means of predetermined thermodynamic models, pressure and temperature data are used to ascertain the proportions of first and second main component in bottom product streams.

The present invention relates to a process for producing hydrogen and for separating carbon dioxide from synthesis gas using a physical absorption medium. The process comprises the steps where the synthesis gas and the absorption medium are cooled; carbon dioxide is removed from the cooled synthesis gas via the cooled absorption medium in a physical absorption step at elevated pressure; laden absorption medium is treated in a plurality of flash stages, wherein co-absorbed carbon monoxide, hydrogen and carbon dioxide are separately removed from the laden absorption medium; hydrogen is separated from synthesis gas freed of carbon dioxide in a physical separation step, wherein hydrogen as product gas and an offgas comprising hydrogen, carbon monoxide and carbon dioxide are obtained; product gas hydrogen and carbon dioxide are discharged from the process. The invention further relates to a plant for performing the process.